Method of producing substituted guanidines



Patented Mar. ie, 1931 omrsn stares rarer 'FFICE HERBERT scnorrnonnnnmn-nnrnrcxnnnonr, GERMANY, ASSIGNOR 'IO scnnnmo- 1 KAI-ILBAUM A. a,or BERLIN, GERMANY METHOI P OF PRODUCING SUBSTITUTED GUANIDINES NoDrawing. Application filed September 13, 1928, Serial No. 305,863, andin Germany September 12, 1927.

My invention refers to the production of guanidine derivatives and moreespecially to a method of producing substituted guan1- dines. I i

l/Vhereas cyanamide and mono alkyl cyanamides react with amine saltsveryf'avourably particularly when working in Very concentrated solutiondisubstituted cyanamides do not'react favourably with amines or aminesalts. (Compare Lecher & Demmler Zeitschrift fur physiologische Chemie167,170 (1927)). v

' By the present invention the reaction be-,

tween dialkyl cyanamides and amine salts is caused to take place verysmoothly, and with many derivatives it is not even necessary to increasethe temperature.

The process of manufacture accordingto the invention is by bringing adialkyl cyanamide into reaction with an amine salt in the presence of afree amine.

The reason for the smooth and favourable reaction cannot yet be,definitely explained, possibly an intermediate product of the followingconstitution is produced R R \N/ ({X [I NH wherein R is an alkyl and Xan acid radical which reacts further with the amine.

The following formula shows the structure of the guanidine nucleus,

are however better in the first case.

ing point 118 C. Aniline itself also reacts with dialkyl cyanamidewithout the addition of hydrochloride. The yields of guanidine Example 22.7 parts of diethyl cyanamide, 5 parts of isoamylamine and 7 parts ofisoamylamine hydrochloride give on long standing or after heating forabout one hour to 100 C. the alpha, alpha-dlethyLbeta-isoamyl guanidine,

the hydrohalogen acid salts of which are easily soluble in water and thepicrate of;

the same manner as in Example 2 (with four parts of amine and livepartsof hydrochloride) give alpha alpha-dimethyl-beta-iso-,

The. picrate melts at.

amyl-guanidine Example 4 The method of producing substituted guanidinesby treating a dialkyl cyanamid with a salt of an amine which has atleast one hydrogen atom attached to the nitrogen atom, in the presenceof the corresponding free amine.

HERBERT SCHOTTE.

N511 6 NHfY The following examples illustrate the invention.

' Example 1 5 parts of diethyl cyanamide heated with i 6.5 parts ofaniline hydrochloride and 3 parts of aniline for 10 hours to 100 C. givealpha, alpha-diethyl-beta-phenyl guanidine which is obtained as the oilybase by steam distillation of the deposit after rendering alkaline orwhich can be separated as the pi'crate of melt-

